Six locally acquired dengue fever cases were reported last week, four in Pingtung County and two in Taipei, involving two families, the Centers for Disease Control (CDC) said yesterday.
The Taipei cases were later found to be part of a family cluster of dengue virus infections, as the patients are the grandparents of two brothers living in the Daan District (大安) who suffered the onset of dengue fever last week. The grandparents had experienced an earlier onset of fever than the two brothers, the centers said.
The Pingtung County cases involve three people living in Chaujou Township (潮州), where the fourth person also lives, it said.
As of Monday, in addition to 183 imported cases, 85 locally acquired cases of dengue fever have been reported, of which 76 were in Pingtung County, two in Taipei and seven in Greater Kaohsiung.
The centers said there is a risk that dengue fever could develop into life-threatening dengue hemorrhagic fever, if the patients have antibodies to different types of dengue virus from earlier infections, as well chronic diseases such as diabetes, hypertension and heart disease or a compromised immune system.
The agency urged people with chronic illnesses and cancer to take precautions if living in regions where locally acquired dengue infections have been reported.
Also reported last week were two imported cases of chikungunya, a virus that is transmitted by the bite of infected mosquitoes. It has a similar transmission route as dengue fever. The main symptoms include fever, headache, nausea and vomiting, and severe joint pain that makes the patient stoop over, the CDC said.
It said in both cases, the onset of the disease was in the middle of last month and there was a history of travel to Indonesia. A total of 16 cases of chikungunya have been reported this year, a record high and 3.5 times more than those from the same period in the past five years.